The biothiol glutathione (GSH) plays a crucial role in regulating redox homeostasis in living systems and has been shown to be closely related to different types of cancer. Thus, there has been much interest in the development of fluorescent probes for GSH in live cells. With our on-going interest in the development of luminescent transition metal complexes for bioimaging and photodynamic therapy (PDT), we functionalized rhenium(I) complexes with a dinitrophenylsulfonamide moiety to afford a new class of GSH-responsive phosphorogenic reagents. Upon reaction with GSH, these complexes exhibited significantly enhanced emission intensities and singlet oxygen photosensitization capability. Modification of the complexes with a tosylamide unit also resulted in probes with endoplasmic reticulum-targeting ability. These complexes are promising GSH-sensitive reagents for bioimaging and organelle-targeted PDT applications.

We thank the Hong Kong Research Grants Council (Project No. CityU 11300017, CityU 11300318, CityU 11300019, CityU 11302820, and T42-103/16-N) for financial support.

Reference

Xu, G.-X.; Lee, L. C.-C.; Kwok, C. W.-C.; Leung, P. K.-K.; Zhu, J.-H.; Lo, K. K.-W. Eur. J. Inorg. Chem. 2021, 34, 3432 – 3442.